DESCRIPTION (adapted from the application's abstract): The Minnesota AIDS Clinical Trials Unit (ACTU) requests to continue to be a unit of the Adult AIDS Clinical Trials Group (AACTG). The Minnesota ACTU is committed to the Scientific Agenda of the AACTG, in which they have participated continuously since January 1, 1987. In addition to recruiting and retaining a cohort of new HIV-infected patients in clinical trials (estimated to be 85 patients in main studies and 54 patients in substudies annually), the Minnesota ACTU plans to contribute to the Group Scientific agenda with the following specific aims: (1) to correlate the quantity and replication competence of HIV at the cellular level in lymphoid tissue (LT), peripheral blood fractions and other compartments; (2) to develop more sensitive methods to detect HIV and apply these to selection of more effective therapies; (3) to define the natural history of cytomegalovirus (CMV) disease in the era of potent antiretroviral therapy and determine the best assays (virologic and immunologic) to monitor its clinical course (AACTG 360); (4) to identify and properly manage the patients who are at risk for complications of the dyslipidemias associated with potent antiretroviral therapy; (5) to identify resistant CMV strains and assess their pathogenicity; (6) to study relationships between the production of neurotoxins in plasma and cerebrospinal fluid of HIV-infected patients, neuronal loss as measured by proton magnetic resonance spectroscopy and the development or progression of HIV-associated dementia (HAD); and (7) to understand and characterize pharmacokinetic behavior, including drug-drug interactions, of antiretrovirals and other HIV-related drugs in biologic fluids. To help achieve these specific aims, the Minnesota ACTU has both Virology and Pharmacology Advanced Technology Laboratories (ATL). The Virology ATL is focusing on quantitation and characterization of HIV in lymphoid tissue and other body compartments. This laboratory also has expertise in HIV and CMV resistance. The Pharmacology ATL is developing assays for simultaneous determination of levels of protease inhibitors and measurement of intracellular antiretroviral anabolites. The Nebraska subunit has a special interest in neuroAIDS and has identified neurotoxins putatively responsible for pathology in HAD. The Iowa subunit has expertise in the detection of hepatitis C and will be collaborating in studies of the pathogenesis of coinfection with HIV and hepatitis C.